Detect Windows OS

[Parse]

Hi,

What is the smallest way to detect whether the computer you're running on is win9x or winNT+.

Code Select Expand

call [GetVersion]
cmp eax, 80000000h
jb short win9x

that's what i've got So Far.

edit: Ok not the smallest way, but another way. I also use the checking of whether the RegisterServiceProcess Api can be found.

I'm looking for a better way. Oh, and not using GetVersionExA

[P1]

In real estate, it's location, location, location.

In programming, it's the need, the need, the need.

Please help us with the context of this request and the need.  Because I have seen too many times, where we are guessing at what you want, when we know the need, we can give a more appropiate answer.

Regards,  P1  :8)

[diablo2oo2]

one way is to check for an API which is only avaible on NT systems.

Code Select Expand

invoke GetModuleHandle,chr$("kernel32.dll")
invoke GetProcAddress,eax,chr$("UpdateResourceA")
.if eax==0
;not NT system...
.endif

[Parse]

In real estate, it's location, location, location.

In programming, it's the need, the need, the need.

Please help us with the context of this request and the need.  Because I have seen too many times, where we are guessing at what you want, when we know the need, we can give a more appropiate answer.

Regards,  P1  :8)

I'm just trying to optimize a program. It branches off at some point, where on one side it uses NT only Apis, and on the other 9x apis. It's just for fun and to learn something. I was hoping you guys could show me some cool secret asm tricks to do this.

[Petroizki]

Code Select Expand

assume fs:nothing
cmp dword ptr fs:[30h], 0
js win9x

10 bytes...  :lol

[Mark Jones]

Code Select Expand

assume fs:nothing
cmp dword ptr fs:[30h], 0
js win9x

10 bytes...  :lol

Hi Petroizki, what does that compare against, Win9x and NT? What about 2K and XP? :)

[Petroizki]

Hi Petroizki, what does that compare against, Win9x and NT? What about 2K and XP? :)

NT+ vs. 9x.
2k and XP are NT derived OS's, so they are identified as NT too. :wink